Pressure relief for a passenger side air bag

Abstract

An air bag system for an assistant driver's seat comprises a housing including an open face to allow air bag deployment, an air bag folded in the housing, a gas generator secured to the rear wall of the housing opposite to the open face, first outlets formed in the gas generator to allow gases to flow into the air bag stored in the housing, second outlets formed in the gas generator to allow the gases to flow out of the housing, a passage defined in the housing to provide a communication between the second outlets and the outside of the housing, and a release mechanism situated in the passage for allowing the gases to flow from the gas generator into the outside of the housing through the passage when the pressure of the gases flowing through the second outlets exceeds a predetermined level.

I claim: 
     
       1. An air bag system for a passenger seat, comprising: a housing having an open face to allow air bag deployment, and a rear wall at a side opposite to the open face;   an air bag folded in said housing;   a gas generator secured to the rear wall of the housing;   first outlets formed in the gas generator to allow gas to flow into said air bag folded in the housing;   second outlets formed in said gas generator to allow the gas to flow out of said housing;   a passage defined in said housing to provide a communication between said second outlets and an outside of the housing; and   relief means situated in the passage for allowing the gas to flow from said gas generator into the outside of the housing through the passage when a pressure of the gas flowing through said second outlets exceeds a predetermined level, said relief means including an O-ring disposed to close the passage, and an engagement portion situated in the passage for preventing outward movement of the O-ring from the housing, said O-ring being disengaged from the engagement portion under the pressure of the gas to open said pressure when the pressure of the gas from the gas generator exceeds the predetermined level.   
     
     
       2. An air bag system for a passenger seat, comprising: a housing having an open face to allow air bag deployment and a rear wall at a side opposite to the open face;   an air bag folded in said housing;   a gas generator secured to the rear wall of the housing;   first outlets formed in the gas generator to allow gas to flow into said air bag folded in the housing;   second outlets formed in said gas generator to allow the gas to flow out of said housing;   a passage defined in said housing to provide a communication between said second outlets and an outside of the housing;   a retainer for mounting the gas generator to the housing; and   relief means situated in the passage for allowing the gas to flow from said gas generator into the outside of the housing through the passage when a pressure of the gas flowing through said second outlets exceeds a predetermined level, said relief means having a metal plate for constituting the retainer and positioned to close the passage, said metal plate being deformed by the gas to largely open the passage when the pressure of the gas exceeds the predetermined level.   
     
     
       3. The air bag system of claim 1, wherein said retainer has a contact portion held in close contact with said gas generator to close said second outlets, projections positioned adjacent to said contact portion, and openings formed in said projections, said contact portion being moved off said gas generator under the pressure of the gas to provide a communication between said second outlets and said openings so as to open said passage when the pressure of the gas from said gas generator exceeds said predetermined level.